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Topic: Class A Handling issues (Read 5233 times)

I am trying to find something to improve the handling of my Thor Hurricane 31s. At highway speeds, 55+, it tends to wander in the lane and is pushed around by crosswinds and passing semis. Regarding the highway speed: typically the higher the speed the worse the handling. A note on that, I don't like to go over 65 mph, mainly as a mileage consideration. I have been researching stabilizers, track bars, etc... on the internet and various Forums such as the this forum (probably the best IMHO), the RVUSA Forum, Thor Forum, iRV2 Forum, Camping World/Good Sam plus reading about Super Steer, Roadmaster, Blue-Ox, Safe T Steer, and various Ford F53 with a Class A solutions. What I have discovered is that the solutions, advice, and recommendations run the gamut from minor to major. Some say lower the tire pressure below the recommended or raise the tire pressure to 110 psi, the tire rims are too narrow, get different tires, add shocks or air bags, a steering stabilizer will fix it, or maybe not, a rear track bar is needed, a front track bar is needed, a front or rear track bar won't help. Also there is discussion about how the F53 was not designed to be used for motorhomes, Thor under designs their units, Essentially the information is confusing and frustrating. Are there any owners that have had success with some of the after market solutions? I realize that a person has to pay for good results but there has to be a reasonable, cost effective solution.

You need to get the proper amount of air in your tires. Too much air will cause all the problems you are having. Take your RV to a public scale (Flying J) and get it weighed. Then go to the manufacturers web site and find their tire inflation chart. Most beginners inflate their tires to the number on the sidewall which is dead wrong, that is the maximum you can inflate to not the recommended pressure. That number is different for each RV and each set of tires.

Hi, Thanks for the comment. I have weighed the unit, loaded and with the tow vehicle attached. I have the tire pressure at the recommended pressure plus a couple of pounds. The psi was originally at 105 and I gradually reduced it to what I now have (84) and it did make a difference. Also I have had the front end aligned and that provided some improvement. I still think the handling should be better though.

Yup. Tire pressure first - you did that. There are almost countless conditions that can cause the problems you described. In order, generally, the most helpful for most folks that own a coach on a Ford F53 chassis, is better front and rear swaybars. Then a rear trac bar and steering stabilizer. The newer F53s have front trac bars. There are other aftermarket add-ons you can get as well. Like you seem to have noticed, not cheap. You can try the handling fix as talked about at length on the IRV2 forum; zero cost, and if it helps, that's one thing you know you need to address, sway bars. That was my biggest improvement, then a rear trac bar and steering stabilizer.Make sure you cover your butt about the warranty, if you make changes to the chassis.

We have a 2008 Thor Outlaw that is 37 foot long on the F53 Chassis.When we bought it and drove it home from La. , It was scary !! 65 or 70mph and it would starttipping back and forth untill you slowed down to under 60mph.. And if a semi-trailer passed you, it would shove you over 6-8 feet ! Very very Scary feeling..

Well after I got it home and started checking it out, I found the rear sway bar was unhooked at one end andthe bracket was bent and there was NO bushings left in the brackets.. So I bought new bushings, straightened bracket out and rebolted the whole thing back on and lock-tited the bolts.. Huge difference ! Much much better with no tipping back and forth and only getting pushed 2-3 feet by passing Semi's..

Next, I did the cheap no cost mod. I moved the sway bar arms from the outside hole to the innner holes as many have doneand again, A big differnce.. Much more stable ride and now passing Semi's hardly bother us at all.... I still feel that they need a larger rear sway bar as the rig is so tall (13 foot) and still moves more than I like, But I can live withwhat I have now...

I dont know if your newer Thor F53 has the sway bar on the rear or not. But if not, that is something I would strongly recommend..And our rig weighs about 24,000lbs and we run 80psi in our tires..

Hi, Thanks for the comment. I have weighed the unit, loaded and with the tow vehicle attached. I have the tire pressure at the recommended pressure plus a couple of pounds. The psi was originally at 105 and I gradually reduced it to what I now have (84) and it did make a difference. Also I have had the front end aligned and that provided some improvement. I still think the handling should be better though.

You are doing things right. Air pressure, then a good alignment. I did the same thing to my 2007 Damon on a 20,500 pound chassis. It was much better but when I added the rear trac bar it was huge as far as handling side winds and trucks. I never did the cheap handling fix because on my coach at least sway was not a problem.

I am weighing in about 19000 lbs fully loaded pulling a single axle trailer F53 Chassis... I done the CHF on both the sway bars..Installed Firestone Air bags and run tire pressures at 65lbs ....even the DW enjoys driving the rig now...

Had a similar situation with my Damon UltraSport. Went to a super steer shop Mainline Truck and Trailer in Cleveland Ohio. Had a road performance assessment done. They road test the coach. Check all the suspension parts and weight all 4 corners of the coach. Then make recommendations. I had tried to self diagnose with no luck. Their recommendations are rated as what is most important. Best $145.00 I ever spent on the coach. If they do the work all or part of the fee is applied to the final bill.

Well, I will try this again since my previous reply apparently didn't get sent. First I want to thank Gary for the link to the the article in the Library. It was very helpful and cleared up a lot of things for me. Also want to thank everyone else for their comments. I am apparently at the beginning of a steep learning curve. I did some stretching exercises and then crawled under the the motorhome to see what is actually there. It looks like there is a factory installed sway bar on the rear axle and also one on the front. Additionally it looks like there is a factory installed track bar on the front. There is a bar that connects from the passenger side frame to the front axle, with appropriate bushings, and I assume that is a track bar. For additional info, both the coach and the chassis are 2017 models. I am starting to come to the conclusion that perhaps I should first try a rear track bar or a supplemental rear sway bar. The sway bars look to be pretty substantial though with the front thickness measuring 1 3/4" and the rear at 1 5/8". The front track bar appear to have a thickness as least as great as the front sway bar. Another possibility is perhaps after market springs or shocks but after reading Gary's article I am not sure that would provide the improvement I want. Opinions are welcome.

I think your problem is all the crap that was added on. A stock RV should not need add on accessories to make it drive properly.

I don't think anything has been done to his yet as it is a unfortunate reality that the manufactures don't do a better job. WinterAdverse, The sway bars control side to side roll or rocking. One cheap upgrade (if you don't already have them) is polypropylene sway bar bushings as they are firmer than the rubber ones. The track bar for the back will stabilize the side to side (fish tailing) caused by the rear overhang.Speaking of that watch out for "tail swing" when maneuvering in tight places, like gas stations. Don't get to close to the pumps and don't turn to quick or sharply when pulling out. Bill

A stock RV should not need add on accessories to make it drive properly.

True - but sadly not the case with the majority of the Ford F53 Chassis' in use. I think it should be on the coach builder to do what is necessary to make things right; Ford has no control over what someone does with their bare chassis, nor can they possibly make "one size fits all". (or in the case of the F53,many sizes).

I guess I'm a slow learner. I have been looking at the CHF solutions and can't help but think that there is some reason the design engineers wanted the sway bar connections in the outside hole rather than the inside. I keep thinking if I move the connections to the inside hole I would be defeating some design/safety issue. That being said, the CHF on the front looks like it is a nonstarter with my chassis. In order to move the connections I would have to raise the ends of the sway bar and that would move the inside holes further away from the ends of the rods that drop down from the frame. It looks like those rods are just too short to make the connection to the inside holes on the sway bar. The rods are already located forward of the sway bar and are slanted towards the sway bar to make the connection at the outside holes. I think the connection rods would be an inch or two short of the inside holes. On the rear sway bar the CHF could be done but I would have to lower the sway bar ends in order to connect to the inside holes. It looks like that is certainly doable without causing any additional issues. That's where the nagging design issue thought come into play. Perhaps I am over thinking this but I can't help but wonder why the connections are in the outside holes to being with. I can understand why there are 2 holes in the sway bars, which is probably to make the bars fit different chassis. If anyone has any design insights I would certainly be interested in seeing them. On another issue I'm looking at rear track bars and I see some connect from the frame to the sway bar bracket that is welded to the axle and some are connected from the frame to bolts on the differential housing. I think the latter would put a lot of stress on those bolts. Does anyone have any thoughts on which is the better approach?

I guess I'm a slow learner. I have been looking at the CHF solutions and can't help but think that there is some reason the design engineers wanted the sway bar connections in the outside hole rather than the inside. I keep thinking if I move the connections to the inside hole I would be defeating some design/safety issue. That being said, the CHF on the front looks like it is a nonstarter with my chassis. In order to move the connections I would have to raise the ends of the sway bar and that would move the inside holes further away from the ends of the rods that drop down from the frame. It looks like those rods are just too short to make the connection to the inside holes on the sway bar. The rods are already located forward of the sway bar and are slanted towards the sway bar to make the connection at the outside holes. I think the connection rods would be an inch or two short of the inside holes. On the rear sway bar the CHF could be done but I would have to lower the sway bar ends in order to connect to the inside holes. It looks like that is certainly doable without causing any additional issues. That's where the nagging design issue thought come into play. Perhaps I am over thinking this but I can't help but wonder why the connections are in the outside holes to being with. I can understand why there are 2 holes in the sway bars, which is probably to make the bars fit different chassis. If anyone has any design insights I would certainly be interested in seeing them. On another issue I'm looking at rear track bars and I see some connect from the frame to the sway bar bracket that is welded to the axle and some are connected from the frame to bolts on the differential housing. I think the latter would put a lot of stress on those bolts. Does anyone have any thoughts on which is the better approach?

Hear is a design insight. Do the CHF or spend a couple thousand on a stiffer sway bar that does exactly the same thing. I don't know how many thousand have done this with NO PROBLEM.Pick a track bar no one is having any problems with either attachment method. Bill

I guess I'm a slow learner. I have been looking at the CHF solutions and can't help but think that there is some reason the design engineers wanted the sway bar connections in the outside hole rather than the inside. I keep thinking if I move the connections to the inside hole I would be defeating some design/safety issue. That being said, the CHF on the front looks like it is a nonstarter with my chassis. In order to move the connections I would have to raise the ends of the sway bar and that would move the inside holes further away from the ends of the rods that drop down from the frame. It looks like those rods are just too short to make the connection to the inside holes on the sway bar. The rods are already located forward of the sway bar and are slanted towards the sway bar to make the connection at the outside holes. I think the connection rods would be an inch or two short of the inside holes. On the rear sway bar the CHF could be done but I would have to lower the sway bar ends in order to connect to the inside holes. It looks like that is certainly doable without causing any additional issues. That's where the nagging design issue thought come into play. Perhaps I am over thinking this but I can't help but wonder why the connections are in the outside holes to being with. I can understand why there are 2 holes in the sway bars, which is probably to make the bars fit different chassis. If anyone has any design insights I would certainly be interested in seeing them. On another issue I'm looking at rear track bars and I see some connect from the frame to the sway bar bracket that is welded to the axle and some are connected from the frame to bolts on the differential housing. I think the latter would put a lot of stress on those bolts. Does anyone have any thoughts on which is the better approach?

As far as the track bar goes - the longer the bar, the better - don't think either location is problem - they have been used on many ford chassis and for many miles/years without issue - as have the swaybar chf changes. No one has ever gotten answer to the question as to "why two holes". Again, been in use for several years and many miles on many an F53 chassis.

Thanks for the comments and insights. Based on the comments the track bar design that connects to the sway bar bracket is the longer of the track bar designs so that sounds like the way to go for the best results. I still have concerns about the CHF but will probably try it on the rear when the weather warms a bit. I can't see that the CHF for the front can be done unless I find some longer rods to connect the frame to the sway bar. Anyone know if those are available from any aftermarket suppliers. I have entertained the idea of swapping the rear rods and front rods since the rear ones look like they are longer than they need to be. I always think that just because something has always been done doesn't necessarily mean that it is the right thing to do. Thanks again for the comments.

Thanks for the link for the adjustable links. I will look at that. Much appreciated.

Trying to figure out why you need longer links? take both links loose and the sway bar will rotate down. The links control the location of the sway bar. Replace the bushings in the links with polypropylene bushings as they are harder and will give better control.Bill

As stated in a previous post: "The CHF on the front looks like it is a nonstarter with my chassis. In order to move the connections I would have to raise the ends of the sway bar and that would move the inside holes further away from the ends of the rods that drop down from the frame. It looks like those rods are just too short to make the connection to the inside holes on the sway bar. The rods are already located forward of the sway bar and are slanted towards the sway bar to make the connection at the outside holes. I think the connection rods would be an inch or two short of the inside holes." I may try the CHF on the front without the adjustable links just to see if it is possible if I feel adventurous and have time to spare. First I want to measure the links and the approximate length required with the CHF but that will have to wait till the weather is a bit warmer.

Well I took advantage of a nice day and performed the CHF on the rear of the Motorhome. It actually wasn't too bad, once I had all the tools I needed close by. It was a good workout for an old man. I was really surprised that the nuts and bolts were metric, 16 & 18mm to be exact. For something made it the US I was expecting and was prepared for the old SAE stuff. That required a trip from the storage unit to home and back. I looked at the front end and did some measuring and realized that the CHF is not possible unless I get some longer link rods. The installed rods measure 11 inches bolt to bolt. As I mentioned before I would need to raise the sway bar to make the CHF and that would move the inside holes away from the link rods, which would have to be pushed toward the back of the chassis to reconnect to the sway bar inside holes. The link rods are already slanted back towards the rear to connect to the sway bar outside holes. My rough estimate is the link rods would have to be 12 to 12 1/2 inches to allow for the reconnect. My thinking is to forget about the CHF on the front and see how the MH handles with the the rear CHF. If it is not what I want then to try a steering stabilizer instead of the CHF. I haven't test drove the MH yet since the rear CHF because we have a cold front coming through with high wind warnings. I hope to get it out in a couple of days.

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2017 Thor Hurricane 31STowing 2013 Honda CRVHome - Western SD

rls7201

Glad you elected to make adjustments before buying some of the stuff being marketed to us RVers.Here's one more adjustment to make before you spend a fortune on stuff.Make sure the toe-in is set to 1/16"-3/32" toe-in. It makes a huge factor in steering wheel response. Believe it or not, if it feels like something is loose, it may just be toe-in.Toe in can be measured using two straight pins, stuck in the center of the tread, and a tape measure. Have you ever seen a tape measure out of calibration? GRIN.... Think about all those high end, out of calibration, front end lazer alignment machines and the unqualified personal using them. GrrrrrrrrrrStick the pins in the center/front of the tread, measure. Roll RV tires back 180 degrees and measure again. Front measurement should be 1/16"-3/32" less than rear. How simple is that.If the toe-in is off, then the work begins. The adjustment is on the right tie rod end. Wrench sticking up on top of the sleeve nut, push back for more toe-in. Oh yeah, loosen the clamp first. Wipe sweat out of eyes.

Thanks for the tip on the toe-in. I have seen that discussed in other places and wonder how that would affect the tire wear. Have you noticed any unusual or increased wear on the tires after getting the toe-in adjusted?

I am weighing in about 19000 lbs fully loaded pulling a single axle trailer F53 Chassis... I done the CHF on both the sway bars..Installed Firestone Air bags and run tire pressures at 65lbs ....even the DW enjoys driving the rig now...

reniram---How did you arrive at 65 pounds? That seems awful low. What size tires are you running?